Processes for the preparation of resinous bodies for adherent metallization comprising treatment with manganate/permanganate composition

Abstract

Securely bonded layers of electroless metals on bodies having a resinous surface are provided after first contacting the surface of the body with a highly active, easily controllable, readily disposable composition comprising water, permanganate ion and manganate ion, the molar ratio of manganate to permanganate being up to about 1.2 and the composition having a pH controlled in the range of 11 to 13. Resinous surfaces so treated are neutralized in a process including treatment with hydrazine in order to yield metallized resinous surfaces exhibiting superior peel strengths following electroless metal deposition.

We claim: 
     
       1. In a process for producing a securely bonded layer of metal on a resinous surface by electroless metal deposition the improvement which comprises contacting the resinous surface, prior to electroless metal deposition, with a composition comprising water, permanganate ion and manganate ion in the molar ratio of manganate ion to permanganate ion of up to 1.2, said composition having a pH in the range of 11 to 13, followed by removal of substantially all oxidation by-products of said contacting from the resinous surface prior to electroless metal deposition. 
     
     
       2. A process as defined in claim 1, wherein said oxidation by-products are removed in a multi-step neutralization process including a first treatment with an acid complex reducing agent and a second treatment with an alkaline complex reducing agent. 
     
     
       3. A process as defined in claim 1, wherein said oxidation by-products are removed in a neutralization process comprising treatment of said resinous surface with an aqueous solution comprising hydrazine. 
     
     
       4. A process as defined in claim 3, wherein said neutralization consists of a multi-step process including treatment of said resinous surface with a solution comprising an acid complex reducing agent prior to said treatment with hydrazine. 
     
     
       5. A process as defined in claim 4, wherein said solution comprising hydrazine also includes at least one sequestering agent capable of forming soluble complexes with manganese ions. 
     
     
       6. In a process for producing a securely bonded layer of metal on a resinous surface by electroless metal deposition, the improvement which comprises contacting the resinous surface, prior to electroless metal deposition, with a composition comprising water, permanganate ion and manganate ion in the molar ratio of manganate ion to permanganate ion of up to 1.2, said composition having a pH of about 12.5, followed by contacting said resinous surface with a first neutralizing solution comprising water, a strong acid and a sequestering agent capable of forming soluble complexes with manganese ions, followed by contacting said resinous surface with a second neutralizing solution comprising water and hydrazine. 
     
     
       7. A process as defined in claim 6, said second neutralizing solution also containing at lest one sequestering agent capable of forming soluble complexes with manganese ions. 
     
     
       8. A process as defined in claim 7, wherein said first neutralizing solution comprises water, hydrochloric acid and hydroxylamine hydrochloride, and said second neutralizing solution comprises water, hydrazine, ethylenediaminetraacetic acid, triethanolamine, and sodium carbonate. 
     
     
       9. A process as defined in claim 7, including the additional steps of water-rinsing between permanganate treatment and first neutralization and between first and second neutralizations. 
     
     
       10. A process for producing a securely bonded layer of metal on a resinous surface by electroless metal of deposition comprising the stpes of: a. oxidizing the resinous surface with a composition comprising water, permanganate ion and manganate ion in the molar ratio of manganate ion to permanganate ion of up to 1.2, said composition having a PH of from about 11 to about 13;   
     
     
       1 b. neutralizing the oxidized resinous surface with a first solution comprising an acid complex reducing agent; c. further neutralizing the treated surface of step (b) with a second solution comprising hydrazine; and metallizing the surface in an electroless metal deposition bath.   
     
     
       11. A process according to claim 10 including the additional step of catalyzing the neutralized surface of step (c) prior to the metallizing of step (d).